PTC Heater Circuit

HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: PTC Heater Circuit
- PTC Heater Circuit

DESCRIPTION

The air conditioning amplifier assembly sends operation signals to the No. 1 integration relay when quick heater assembly (PTC heater) operation conditions are met. Based on the signals from the air conditioning amplifier assembly, the relays in the No. 1 integration relay turn on, and power is supplied to the quick heater assembly (PTC heater) installed in the air conditioning radiator assembly.

Quick Heater Assembly (PTC Heater) Operation Condition





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

1. PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Air Conditioner / Active Test.

(e) Check the operation by referring to the table below.

Air Conditioner





OK:

Quick heater active level changes normally.

NG -- INSPECT QUICK HEATER ASSEMBLY

OK -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Symptom Related Diagnostic Procedures

2. INSPECT QUICK HEATER ASSEMBLY

(a) Remove the quick heater assembly Removal.





(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





NG -- REPLACE QUICK HEATER ASSEMBLY Removal
OK -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (QUICK HEATER ASSEMBLY - BODY GROUND)

(a) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (QUICK HEATER ASSEMBLY - NO. 1 INTEGRATION RELAY)

(a) Disconnect the A19 quick heater assembly connector.

(b) Disconnect the 1H No. 1 integration relay connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

5. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - POWER SOURCE)

(a) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

6. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - BODY GROUND)

(a) Disconnect the 1G No. 1 integration relay connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

7. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - NO. 1 INTEGRATION RELAY)

(a) Disconnect the L17 air conditioning amplifier assembly connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

8. CHECK NO. 1 INTEGRATION RELAY

(a) Replace the No. 1 integration relay Removal.

HINT
Since the No. 1 integration relay cannot be inspected while it is removed from the vehicle, replace the No. 1 integration relay with a new or a known good one and check that the condition returns to normal.

(b) Check if the same problem occurs again.

OK:

Same problem does not occur.

NG -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Symptom Related Diagnostic Procedures

OK -- END (NO. 1 INTEGRATION RELAY WAS DEFECTIVE)